Polymer microvoid formation during

Microvoid Formation during Sample Preparation of Polymer Glasses. 

Density measurements were done on different composite samples before the tensile test and immediately after they reached the yield point. In each case we observed density decrement, which was of the order of 0.5 t i% and which could be attributed to microvoid formation during the test the decrement was higher in the case of composites containing SIC treated beads. In the case of yield stress Oy, the effects of the filler should depend on the filler surface area and therefore related to 02/3, Smith and Nicolais and Narkis theoretically suggested lower limit value of Oy, attributing the loading capacity to the polymer only. If n spherical particles of radius r are dispersed in the unit cube the cross section of the continuous phase is A = 1 - IT-(nr) 2 and the volume fraction is 0 = jn(nr). After substitution we get A = 1 - (3/4n) / 0 / =... 

Cavitation corresponds to formation of microvoids in the amorphous layers confined between crystalline lamellae. According to a general view (Pawlak and Galeski 2005), during stretching of semi-crystalline polymers there is a competition... 

---